Wildfires in the United States have increased in both frequency and size due to factors such as climate change and droughts, leading to increased dryness in forest soils and vegetation. Additionally, the trends include suburban sprawl which has caused more people to live and recreate in wildland areas, increasing the risk of human-caused fires and also increasing the risk of damage to structures placed into wildland areas. Further, forestry practices since 1900 include suppression of natural fires resulting in many wildland forests becoming more dense with trees and brush. Thus, fires become more destructive.
In many cases, wildland fires burn for many days or even weeks or months. The direction of the fire can be generally predicted and homeowners in the potential path of the fire can be warned and asked to evacuate. Generally, protecting structures in wildlands includes firefighters and homeowners constructing fire breaks, as well as firefighters or homeowners spraying water onto flammable structures in advance of a fire. Water has certain advantages in firefighting by cooling flammable materials and also displacement of oxygen that is necessary for combustion of fuel. However, once homeowners are evacuated, they are unable to continue spraying water onto their structures.
Water evaporates quickly from dry materials. Further, continuously spraying water on combustible materials such as a home is labor-intensive, taking up firefighter's time that is better spent elsewhere, and dangerous to firefighters as well when the fire is nearby.
It would be desirable to provide to homeowners (and firefighters) with a fire protectant product that can be applied to potentially combustible materials in advance of a fire or evacuation order, which would also stay intact on the combustible material for a period of days to weeks, and provide excellent fire protection during that entire time without further attention or application. It is also desirable that the fire protectant product would retain its fire protecting function after application, even after drying or dehydration of the product. It would also be desirable that the fire protectant product would be biodegradable and nontoxic, and also that it can be easily removed from the combustible material by a water wash once the fire danger is passes, or easily removed from the material once it has been combusted.
Firefighting foams have been used for many years. Firefighting foams can work by suppressing and preventing air from mixing with flammable vapors, separating flames from the fuel's surface, and cooling the fuel and its surface through the action of water in the form. The foam is creating by mechanically mixing air with a surfactant and other materials in water.
Hydrolyzed protein surfactant foams are known for fighting fires and are made from hydrolyzed granular keratin proteins (hoof and horn meal, chicken feathers, etc.). They include stabilizing additives and inhibitors to prevent corrosion, resist bacterial decomposition and to control viscosity. Fluoroprotein foams have fluorochemical surfactants which enhance performance by providing faster knockdown and better fuel tolerance. Film forming fluoroprotein foam (FFFP) that are designed to combine the fuel tolerance with increased knockdown power. Aqueous film forming foams AFFF provides fast knockdown of hydrocarbon fuels. Alcohol resistant film forming fluoroprotein foams (AR-FFFP) are produced from protein foam, fluorochemical surfactants and polysaccharide polymers. They are capable of producing a tough membrane that separates the foam from the fuel and prevents the destruction of the foam blanket.
However, none of the foams currently available provide the combination of properties to make a fire protectant product that can be applied to potentially combustible materials in advance of a fire or evacuation order, that will remain intact on the combustible material for a period of days to weeks, and provide excellent fire protection during that entire time without further attention or application, and which is also biodegradable, nontoxic, and can be easily rinsed off when fire protection is no longer needed.
The present invention is directed toward overcoming one or more of the problems discussed above.